Lunati cam inquiry

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Here is a list of Racer Brown cam profiles; they aren't complete specs as the LSA is not given. Something like the ST-21, ST-22, ST-23 range look interesting.

Profile

Are you wanting to keep the TC stall speed down to some general level?
 
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OK, never mind, I see you are looking for a reasonably wide torque range; makes perfect sense for a flexible engine for the street. From personal experience, a 2500-6500 torque band is a great thing to have for general engine use. I think you are doing yourself a favor to keep the low end down in that range. But, your gearing will make up for it some.

Are you running an OD trans by any chance? Just thinkin' about highway cruising.. if that is in your planned usage.

As has been said, a roller will do even better but that is a pretty big jump in pricing.
 
nm9stheham said:
Are you running an OD trans by any chance? Just thinkin' about highway cruising.. if that is in your planned usage.

Won't be much highway, mostly secondary roads with a 55 zone(yeah right, lol). :D

As has been said, a roller will do even better but that is a pretty big jump in pricing.
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Well, a roller would be awesome, but I understand (if I'm understanding it correctly) would require lifter bore work etc. Price at this time would probably nix that idea.
 
Ok, so your gearing is not a big factor. It would get tiring at 70 mph after a while!

I forgot to post the Racer Brown link; I'll edit that into post #27.
 
And the lifter bore re-work is for the hydraulic rollers, when the waist band on the lifter peeks above the edge of the chamfer on the lifter bore. Not all blocks have deep lifter bore chamfer issues, and if you lift is low, then it is less likely to happen, or not at all.

It can be universally solved with a sold roller so that issue can be bypassed completely.
 
Sure (Is this a trick question? LOL) There have been a few threads about this roller and lifter bore issue, and when all else fails, the solution is the solid roller. I think Ironmike was one of the folks who went through this.
 
nm9stheham said:
Sure (Is this a trick question? LOL)
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LMAO, no, it just never crossed my mind.

You gots to remember you're dealing with a person here that has never ventured into that territory.

If a solid roller will work, then what am I waiting for?

That changes the whole picture. If I understand, roller cams aren't subject to lobe failure during breakin and don't 'require' special oils to keep them alive.

Sound right??
 
'pzactly! Well, not AS prone to lobe failure... anything can go 'kablooie'!

And since the profiles can be steeper, you can more easily get that wider RPM range engine operation: more lift for higher RPM power, with a lower duration that helps low RPM torque. I'd like to hear what you come up with for solid rollers.
 
Put the MP 528 in it and never look back.
 
fishy68 said:
Completely agree.

Bruce the Lunati cam your looking at is a decent street cam but it's not going to make the power a solid does and I assume your installing it to gain power. What solid cam do you have? Remember a solid cam is generally equal to a hyd cam that has about 8-10 degrees more duration. When you lash a solid you also lose a little lift so figure that into the equation
I'm with Tracy,on this one...A good moderate solid flat tappet,does everything better,than a hydraulic flat tappet..(especially on ported heads,with a budget...) Tracy has had good luck,with solids..I had the same,on Rat motors ,Bruce... A solid can REALLY wake up the torque curve,over a hydraulic cam.(Just my opine,...)
If you want the most band for the buck call Jim at Racer Brown up at 410-866-7660 and tell him exactly what you have and exactly what you want to do and he'll grind you a solid that'll make great power and be as street friendly as you could ever imagine. Like I always say, if in doubt let the guy that's been grinding them for 40+ yrs. decide for you
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I notice that the Comp Cam spec that RF360 listed above shows the valve timing events at .015" of valve lift, not the normal .004" to .006" (which varies between manufacturers). I am not sure if this is a Comp thing or is normal on all roller specs.....??
 
I think the lift that they measure from varies by lifter type. Solid flat tappets and solid rollers are usually at slightly more lift, hydraulics less. Probably a combination of the take up ramps and lash figures.

Personally I won't go solid roller without bushing the lifter bores. Street is as important as race as far as the "whys".
In terms of potential cam choices - they are all very similar. Given the mild performance, and wide operating range, pick one. All of them will work well and the best might only be "best" by a 5-6%.
 
moper said:
Personally I won't go solid roller without bushing the lifter bores. Street is as important as race as far as the "whys".
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I must be missing something (seriously) ..... what 'why' beyond a waist band peeking above the lifter chamfer?
 
moper said:
I think the lift that they measure from varies by lifter type. Solid flat tappets and solid rollers are usually at slightly more lift, hydraulics less. Probably a combination of the take up ramps and lash figures.
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You are right... I dug into the Crane Master Profile catalog just now, and they do indeed measure advertised durations at different lifts. Their solid rollers are measured at .015" to up to .0245" lift. Solid flat tappets are different too. Tnx.
 
nm9stheham said:
I must be missing something (seriously) ..... what 'why' beyond a waist band peeking above the lifter chamfer?
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If you're at all familiar with the quality of factory machining of the decks, bores, mains, etc, consider the relationship of the lifter bores to the camshaft centerline too. misalignment can lead to stress on the lifters (BIG concern if this is a street engine with alot of idle time and a mid-size or larger cam), harmonic issues, and loss of power and rpm peak. The "waistband" issue can be solved with tubing the block. Tubing also directs the available oil to the lower end rather than trapping it and losing it past worn lifter bores. That issue can also be solved with certain solid body lifters, however this also adds a bit of weight - something any roller tappet does anyway - and does nothing if there is a valvetrain failure at rpm and all the oil goes out of the open bore. So, in order to do all of it: control the leakage past worn bores and the "waistband" issue, give a greater margine of safety in case of upper end failure and the lifter popping out, and correcting the alignment of lifter and cam lobe - I'll spend the $470 to make sure everything is covered.
 
nm9stheham said:
I notice that the Comp Cam spec that RF360 listed above shows the valve timing events at .015" of valve lift, not the normal .004" to .006" (which varies between manufacturers). I am not sure if this is a Comp thing or is normal on all roller specs.....??
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You left out the ST-14. It's the smallest solid flat tappet in the bunch and I run one in my 408 ground on a 108 lca installed at 105. Peak power in my 408 is around 54-5500 but pulls strong to 5700 and I shift at 5800. Very mild idle in my 408. Would probably pull a few more RPM in a 360 if the heads flowed good and idle with authority
nm9stheham said:
I notice that the Comp Cam spec that RF360 listed above shows the valve timing events at .015" of valve lift, not the normal .004" to .006" (which varies between manufacturers). I am not sure if this is a Comp thing or is normal on all roller specs.....??
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Solid cams (flat tappet or roller alike) aren't generally rated at .004-006 gross duration. Generally .015-.020 depending on the manufacturer

Bruce- the oil through part has nothing to do with the cam, it's a function of the lifters so if you find a cam you like just get standard mopar la type lifters and you'll be good to go. Solid rollers are the cats meow on making the most power but keep in mind to run them you need a special distributor drive that's compatible with the billet cam and it's a real good idea to run pressurized rollers so they last a long time on the street. IMO an aggrressivly ground solid flat tappet will get you the best bang for the buck
 
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